Turning off your computer after use is so 20th century. I had read a recommendation from Microsoft before saying that you should use sleep mode if you use your computer at least once a day. Does it hurt the PC in the long run? Well, that will be a very very LONG run.

To me turning off hurts the PC even more. When you turn it back on, it will start booting up your PC and loading everything from HD back to memory. That's the wear and tear of your HD. Sleep mode consume only fraction of the energy to keep the memory active.